package com.atguigu.gulimall.cart.interceptor;

import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberRespVO;
import com.atguigu.gulimall.cart.vo.UserInfoTO;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * 在执行目标方法之前，判断用户的登录状态。并封装传递(用户信息)给controller
 *
 * @author wzb
 */

public class CartInterceptor implements HandlerInterceptor {


    public static ThreadLocal<UserInfoTO> threadLocal = new ThreadLocal<>();


    /**
     * 目标方法执行之前进行拦截
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        UserInfoTO userInfoTO = new UserInfoTO();

        HttpSession session = request.getSession();
        MemberRespVO member = (MemberRespVO) session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member != null) {
            //用户登陆
            userInfoTO.setUserId(member.getId());
        }

        Cookie[] cookies = request.getCookies();
        if (cookies != null && cookies.length > 0) {
            for (Cookie cookie : cookies) {
                // user-key
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)) {
                    userInfoTO.setUserKey(cookie.getValue());
                    userInfoTO.setTempUser(true);
                }
            }
        }
        //如果没有临时用户一定分配应该临时用户
        if (StringUtils.isEmpty(userInfoTO.getUserKey())) {
            String uuid = UUID.randomUUID().toString();
            userInfoTO.setUserKey(uuid);
        }

        //目标方法执行之前
        threadLocal.set(userInfoTO);
        return true;
    }


    /**
     * 业务执行之后: 分配临时用户,让浏览器保存
     *
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

        UserInfoTO userInfoTO = threadLocal.get();

        // 如果没有临时用户，一定要保存应该临时用户
        if (!userInfoTO.isTempUser()) {
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTO.getUserKey());
            cookie.setDomain("gulimall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }

    }
}
